I suspect that USAT will take a look at this year's rankings.
For the Sprint distance, I'd expect those who placed 9-18 in their age group last year in Cleveland are eligible for roll-down spots after this year's Draft-Legal National Championship (provded it stays on). Athletes who confirmed their spot for this year's Grand Final have the option to roll over to next year.
For Olympic distance, the spots roll down all the way to 30th place in each age group. I'd assume they will do that with the finishers of last year's Age Group Nationals.
After the roll-downs, I'd be very surprised if there aren't any spots left for either distance, especially because many people have aged-up this year or will be aging up next year. In the Team USA qualification tab (
https://www.teamusa.org/...am-USA/Qualification) it says they would offer spots to athletes to finished on the podium in their age group in the previous Grand Final (Laussane in this case), but rarely any American athletes make the podium at the Grand Final.
The last resort would be to go through the rankings and roll down to 20th place, and if the spots are still left unclaimed (seems highly unlikely, but that's my opinion- there's still a possibility), I think USAT would just leave those spots unclaimed and send less than 18 athletes to Bermuda.
My strategy is to become an All-American this year in the most difficult age group to do so- the 16-17 age group, which requires a final score in the high 90s-low 100s and has very few ranked athletes, meaning a small number of All-Americans. My advice is to load up on races to rack up more points, try to nab a top-20 spot in your age group (or All-American status, which ever one is better), and hope that there are enough roll down spots.
This is all just a prediction- it just makes sense that USAT would follow through with this. Keep in mind that people might be going to less races, but to be ranked you need to finish just 2 races, so who knows what rankings are going to look like this year.